Use of Nesting Workstations in Assembly

Over the years there has been a fixed idea that components just enter the assembly floor and that assembled products leave it subsequently after certain operations have been executed on such products. Besides, there is a common notion that only small and simple products can be assembled on the so called “assembly nests”; however, the dimensions of objects assembled inside these keep increasing. Nowadays, even an aircraft, a boat, etc. can also be assembled on a moving trolley. This is possible given to the fact that the trolley with the product and with the operators themselves may come to the same storage of parts, while the system does not need to be balanced in time. On the other hand, in assembly nested layouts, the productivity of one operator is usually higher than the productivity on the line station and this because such lines are not often time balanced. Besides, this is also enhanced by the fact that more than one operator can work on a single nest. In this regard, the present paper seeks to identify the ways of combining or assembling components into products, and to analyse quality of the abovementioned assembly approaches.

Rapid On-Substrate Curing of Thick Protective Package Sealing for Automotive Assembly

Protective encapsulant and sealing materials that cure upon delivery are desired for high volume automotive assembly. Unlike many coatings created for electronics, these materials are milimeters thick and have desirable elastomeric properties to withstand decades of stress. While the Automotive Electronics Council (AEC) stress test qualification for integrated circuits (AEC Q100, 1994) may set material temperature resistance at 150C, targets of 200C or 250C are desirable. The ideal polymer exhibits low permeability, effectively creating a barrier to moisture, chemicals, and gases that may emanate anywhere on the chassis. While conventional Buna and Viton rubbers represent a major share of gasketing to protect electronic packages, their design and manufacturing infrastructure cannot meet the pace of prototyping. Polymer compositing with reactive diluents now makes it possible to use CAD fed delivery tools that cure on-contact. Such robotic operated equipment delivers by variable syringe head design on vertical, overhead, or irregular surface contours. Sealant forms that once took months with costly quantity orders, now take seconds in the lab and on the assembly floor. Daetec has created a technology that meets these rapid assembly requirements with properties that exceed the current AEC targets. A complete process will be presented with state of the art LED fiber optic curing on the substrate. Data and application results using comparative specimens will be presented.

Standardization Study of Assembly Floor Slab in Steel Frame Structure

The types of assembly floor slab member and the present development situation of assembly floor slab standardization at home and abroad is presented in the article, as well as assembly floor slab layout schemes and its advantage and disadvantage is presented, and the assembly floor slab standardization scheme is proposed to promote the application of assembly floor slab in steel frame structures.

Case Studies Using Immersive Virtual Assembly in Industry

The Virtual Assembly Technology Consortium is a university/government/industry consortium that seeks to investigate the application of virtual assembly methods in mechanical system assembly processes. In this paper we report three categories of engineering case studies that have been developed by the consortium members over the past two years, describe the overall methodology, and then proceed to feature specific details of two key case studies. An engineering case study has been defined as an account of an engineering activity, event or problem containing some of the background and complexities actually encountered by an engineer, with the objective of providing a medium for learning. The objective of the case studies was to assist consortium members in demonstrating and validating the use of immersive virtual assembly technologies and tools in the simulation of factory floor manufacturing processes. What is of special significance is that instead of modeling simplified problems or perceived representative situations, the case studies were constructed from actual assembly floor projects and situations encountered at industry member sites and with considerable participation from industry engineers and manufacturing shop floor personnel. Based on the success of the case studies, the consortium members inferred that virtual assembly methods are poised to move out of the realm of special projects and test scenarios to deployment in the actual design and manufacturing cycle. However, in order to be truly accepted in industry, there are still issues to be addressed in terms of ease of use, portability of the applications, and preparation of the models for the evaluations. Thus, the case studies added a new dimension to the exploration and understanding of how this new technology could be of practical value in industry.

Une idée monstrueuse: Bicameralism in the Early French Revolution

In the spring of 1789, the members of the newly formed National Assembly tasked itself with the creation of France’s first Constitution. The Assembly set out to reform their country by incorporating enlightenment ideas and newfound liberties. Creating the constitution was not an easy process and the Assembly floor was home to many fierce debates, divides, and distrust amongst the Three Orders: the Clergy, the Nobility, and the Commons. One Constitutional issue was deciding what form the legislature would take. Mounier, Lally-Tollendal, and Clermont-Tonnerre, members of the Committee of the Constitution, who formed a political group known as the ‘Monarchiens,’ proposed a bicameral system that mirrored the two legislative houses of England. Their political opponents fought instead for a single chambered system. When the vote came to the house, bicameralism was defeated in a landslide. My research aims at discovering the motivations of the deputies; Why did they reject Mounier’s bicameralism? Much of the work done on this question so far, particularly that of Keith Michael Baker, argues that the deputies were faced with a choice between radically different conceptions of the purpose of the revolution. However, the work of Timothy Tackett points to the smaller, more contingent issues at play. My work involves the analysis of the assembly debates and the political publications being written by the deputies. Similar to Tackett, I conclude that the deputies were immediately motivated less by grand revolutionary narratives, but instead based their vote on a deep distrust of the aristocracy and political factionalism.